This invention relates to chemical compositions comprising one or more urethane oligomers and coating compositions comprising at least one solvent and the chemical compositions of the present invention. When applied as a coating, these urethane-based chemical compositions impart durable stain-release characteristics. This invention also relates to articles comprising a substrate and on this substrate is a cured coating derived from the coating compositions of the present invention. The cured coating can impart stain-release characteristics to the substrate and resist being worn-off due to wear and abrasion. In another aspect, this invention relates to a process for imparting stain-release characteristics to substrates.
The use of certain fluorochemical compositions on fibers and fibrous substrates, such as textiles, paper, and leather, to impart oil- and water-repellency and soil- and stain-resistance is well known in the art. See, for example, Banks, Ed., Organofluorine Chemicals and Their Industrial Applications, Ellis Horwood Ltd., Chichester, England, 1979, pp. 226-234. Such fluorochemical compositions include, for example, fluorochemical guanidines (U.S. Pat. No. 4,540,497 (Chang et al.)), compositions of cationic and non-cationic fluorochemicals (U.S. Pat. No. 4,566,981 (Howells)), compositions containing fluorochemical carboxylic acid and epoxidic cationic resin (U.S. Pat. No. 4,426,466 (Schwartz)), fluoroaliphatic carbodiimides (U.S. Pat. No. 4,215,205 (Landucci)), fluoroaliphatic alcohols (U.S. Pat. No. 4,468,527 (Patel)), fluorine-containing addition polymers, copolymers, and macromers (U.S. Pat. No. 2,803,615 (Ahlbrecht et al.); U.S. Pat. No. 3,068,187 (Bolstad et al.); U.S. Pat. No. 3,102,103 (Albrecht et al.); 3,341,497 (Sherman et al.); U.S. Pat. No. 3,574,791 (Sherman et al.); U.S. Pat. No. 3,916,053 (Sherman et al.); U.S. Pat. No. 4,529,658 (Schwartz et al.); U.S. Pat. No. 5,216,097 (Allewnert et al.); U.S. Pat No. 5,276,175 (Dams et al.); U.S. Pat. No. 5,725,789 (Huber et al.); U.S. Pat. No. 6,037,429 (Linert et al.)), fluorine-containing phosphate esters (U.S. Pat. Nos. 3,094,547 (Heine et al.); U.S. Pat. No. 5,414,102 (Pohmer et al.); U.S. Pat. No. 5,424,474 (Pohmer et al.)), fluorine-containing urethanes (U.S. Pat. No. 3,987,182 (Gold); U.S. Pat. No. 3,987,227 (Schultz et al.); U.S. Pat. No. 4,504,401 (Matsuo et al.); U.S. Pat. No. 4,958,039 (Pechhold)), fluorochemical allophanates (U.S. Pat. No. 4,606,737 (Stem)) fluorochemical biurets (U.S. Pat. No. 4,668,406 (Chang)), fluorochemical oxazolidinones (U.S. Pat. No. 5,025,052 (Crater et al.)), and fluorochemical piperazines (U.S. Pat. No. 5,451,622 (Boardman)).
Certain of these fluorochemical compositions, such as the fluorine-containing addition copolymers of U.S. Pat. No. 6,037,429 (Linert et al.), may be used on hard surfaces, including for example, ceramics, stone, masonry, wood. U.S. Pat. No. 5,414,102 (Pohmer et al.) and U.S. Pat. No. 5,424,474 (Pohmer et al.) suggest that certain fluorine-containing phosphate esters can be used on hard surfaces, such as, ceramics, stone, masonry, wood, and plastics to repel water, grease, oil, and dirt. These previously known fluorochemical compositions typically have been coated on hard substrates by means of aqueous emulsions.
In coating on hard surfaces, durability of the coating of fluorochemical compositions is a concern. In many cases the fluorochemical compositions exhibit poor durability because the majority of the coated hard surface area is exposed to wear and abrasion from use, cleaning, and the elements. Due to this exposure, the coated composition can be worn-off leaving the hard surface unprotected. Certain fluorine-containing urethanes have been found to provide superior abrasion durability and especially good water- and oil-repellency and stainproofing properties (U.S. Pat. No. 4,504,401 (Matsuo et al.)). These previously known fluorine-containing urethane compositions can be solvent- or water-based. In practice, all of the previously known fluorine-containing urethanes rely on perfluoroalkyl groups having an average of eight carbon atoms to achieve the desired repellency and stainproofing properties.
Although urethanes have been found to be especially durable, improved long-term durability is still needed for many hard surface applications. In particular in the widely used siliceous surfaces, such as ceramic and masonry, a coating composition is needed that imparts longer lasting repellency and stain-proofing and is capable of withstanding repeated abrading and washing.
As indicated above, both solvent- and water-based fluorine-containing urethane compositions have been used to provide water- and oil-repellency to hard surfaces. Since organic solvents pose health, safety, and environmental concerns, the water-based compositions are particularly desirable. However, the previously known compositions are typically aqueous dispersions or emulsions, not solutions; therefore, they require a high temperature cure to impart good repellency properties. In many cases, for example in floors and walls, high temperature curing is not practical or possible. For this reason there is a continuing need for urethanes that do not require costly and energy consuming high temperature cure conditions to impart good repellency properties. Therefore, urethane compositions, including those containing fluorine, that display increased water solubility are needed to eliminate the need for high temperature cure conditions, as well as to increase the ease of preparation and to provide more stable aqueous solutions.
The inventors recognized the need for shelf-stable chemical compositions, including those containing fluorine, that can successfully impart long-term durability, uniform oil- and water-repellency and soil- and stain-resistance. These chemical compositions should be water and organic solvent soluble and should not require high temperatures for curing.
In one aspect, this invention relates to chemical compositions comprising one or more urethane oligomers of at least two repeating units selected from the group consisting of fluorine-containing urethane oligomers and long-chain hydrocarbon-containing urethane oligomers. These urethane oligomers comprise the reaction product of (a) one or more polyfunctional isocyanate compounds; (b) one or more polyols; (c) one or more monoalcohols selected from the group consisting of fluorochemical monoalcohols, optionally substituted long-chain hydrocarbon monoalcohols, and mixtures thereof; (d) one or more silanes; and optionally (e) one or more water-solubilizing compounds comprising one or more water-solubilizing groups and at least one isocyanate-reactive hydrogen containing group.
The silanes are of the following formula (I):
Xxe2x80x94R1xe2x80x94Sixe2x80x94(Y)3xe2x80x83xe2x80x83formula (I)
wherein:
X is xe2x80x94NH2; xe2x80x94SH; xe2x80x94OH; xe2x80x94Nxe2x95x90Cxe2x95x90O; or xe2x80x94NRH where R is a phenyl, straight or branched aliphatic, alicyclic, or aliphatic ester group;
R1 is an alkylene, heteroalkylene, aralkylene, or heteroaralkylene bridging group; and
each Y is independently a hydroxyl; a hydrolyzable moiety selected from the group consisting of alkoxy, acyloxy, heteroalkyoxy, heteroacyloxy, halo, and oxime; or a non-hydrolyzable moiety selected from the group consisting of phenyl, alicyclic, straight-chain aliphatic, and branched-chain aliphatic, wherein at least one Y is a hydrolyzable moiety.
As used herein, the term xe2x80x9coligomerxe2x80x9d means a polymer molecule that consists of at least two repeating (polymerized) units, but up to only a few (for example, from 2 to about 20) repeating units. Each repeating unit comprises a urethane group that is derived or derivable from the reaction of at least one polyfunctional isocyanate compound and at least one polyol. The oligomer is terminated with (i) one or more perfluoroalkyl groups, one or more perfluoroheteroalkyl groups, or one or more long-chain hydrocarbyl groups; and (ii) one or more silyl groups.
The chemical compositions of the present invention, comprising one or more urethane oligomers, impart stain-release characteristics and exhibit durability (i.e. they resist being worn-off) when exposed to wear and abrasion from use, cleaning, and the elements. Therefore, these compositions can be applied as coatings to a wide variety of substrates, for example, by topical application, to impart durable stain-release properties to the substrates. When applied as a coating, the chemical compositions of the present invention can provide a uniform film. Applied as a coating, the chemical compositions of the present invention do not change the appearance of the substrate to which they are applied. Even though the urethane oligomers are of relatively high molecular weight, the chemical compositions of the present invention provide durable stain-release properties comparable to or better than those imparted by the corresponding lower molecular weight compositions containing only the fluorine-containing or long-chain hydrocarbon urethane compound with no repeating unit. In addition, with the chemical compositions of the present invention, there is no need for high temperature curing; they can be cured (i.e., dried) at ambient temperature.
Certain preferred embodiments of the chemical compositions of the present invention include chemical compositions derived from one or more water-solubilizing compounds comprising one more water-solubilizing groups and at least one isocyanate-reactive hydrogen containing group. These preferred embodiments exhibit water solubility, while at the same time providing surprisingly good stain-release properties. These embodiments include, for example, those chemical compositions comprising a urethane oligomer containing one or more solubilizing groups. The solubilizing groups include carboxylate, sulfate, sulfonate, phosphate, phosphonate, ammonium, quaternary ammonium, and the like. These embodiments are particularly well suited for uniform and continuous topical treatments on a variety of substrates, without the need for high temperature curing. This benefit is of particular importance for protecting very large and high mass substrates which are very difficult to heat, such as stone and masonry, and in situations where devices for high temperature cure are not available.
Certain other preferred embodiments of the chemical compositions of the present invention include those compositions comprising terminal Rf groups having from two to six carbons, preferably from three to five carbons, and more preferably four carbons. Even with Rf groups that are relatively short (i.e. less than eight carbons), these chemical compositions, surprisingly, exhibit excellent stain-release. Although compositions comprising lower fluorine content are less expensive, Rf groups shorter than eight carbons typically have been overlooked by those of skill in the art because they have been known to impart inferior oil- and water-repellency and stain-resistance.
Many previously known polymeric, fluorochemical surfactants contain perfluorooctyl moieties. These surfactants ultimately degrade to perfluorooctyl-containing compounds. It has been reported that certain perfluorooctyl-containing compounds may tend to bio-accumulate in living organisms; this tendency has been cited as a potential concern regarding some fluorochemical compounds. For example, see U.S. Pat. No. 5,688,884 (Baker et al.). As a result, there is a desire for fluorine-containing compositions which are effective in providing desired surfactant properties, and which eliminate more effectively from the body (including the tendency of the composition and its degradation products).
It is expected that the oligomeric, fluorochemical compositions of the present invention, which contain perfluorobutyl moieties, when exposed to biologic, thermal, oxidative, hydrolytic, and photolytic conditions found in the environment, will break down to various degradation products. For example, compositions comprising perfluorobutylsulfonamido moieties are expected to degrade, at least to some extent, ultimately to perfluorobutylsulfonate salts. It has been surprisingly found that perfluorobutylsulfonate, tested in the form of its potassium salt, eliminates from the body much more effectively than perfluorohexylsulfonate and even more effectively than perfluorooctylsulfonate. Accordingly, it is believed that such surprising effective elimination from the body will be found with perfluorobutylcarbonate, which is expected to be the ultimate degradation product of compositions comprised of perfluorobutylcarbonyl and perfluorobutyoalkyl moieties.
Other preferred embodiments of the chemical composition of the present invention include those compositions comprising terminal long-chain hydrocarbon groups having 10 to 18 carbons. Long-chain hydrocarbon groups typically have been known to impart poor oil-repellency; however, the chemical compositions of the present invention comprising terminal long-chain hydrocarbon groups having 10 to 18 carbons impart good stain-release properties. For water solubility and performance, long-chain hydrocarbon groups having chain lengths of 12 to 16 carbons are preferred, 12 to 14 carbons being more preferred, and 12 carbons being most preferred.
Another embodiment of the present invention relates to a coating composition comprising a solution comprising the chemical composition of the present invention and a solvent. In this embodiment, it is important that the chemical composition be dissolved in the solvent. When applied to a substrate, this coating composition provides a uniform distribution of the chemical composition on the substrate without altering the appearance of the substrate. A high temperature cure is not required to provide this coating; the coating composition can, be cured (i.e. dried) at ambient temperatures.
This invention also relates to an article comprising a substrate having one or more surfaces and on one or more surfaces of this substrate is a cured coating derived from at least one solvent and a chemical composition of the present invention. After application and curing of the chemical composition, the substrate displays durable stain-release properties.
This invention further relates to a method for imparting stain-release characteristics to a substrate, having one or more surfaces, comprising the steps of:
(a) applying the coating composition of the present invention onto one or more surfaces of the substrate; and
(b) allowing the coating composition to cure (i.e. dry).
Unless otherwise stated, the following terms used in the specification and claims have the meanings given below:
xe2x80x9cAcyloxyxe2x80x9d means a radical xe2x80x94OC(O)R where R is, alkyl, alkenyl, and cycloalkyl, e.g., acetoxy, 3,3,3-trifluoroacetoxy, propionyloxy, and the like.
xe2x80x9cAlkoxyxe2x80x9d means a radical xe2x80x94OR where R is an alkyl group as defined below, e.g., methoxy, ethoxy, propoxy, butoxy, and the like.
xe2x80x9cAlkylxe2x80x9d means a linear saturated monovalent hydrocarbon radical having from one to about twelve carbon atoms or a branched saturated monovalent hydrocarbon radical having from three to about twelve carbon atoms, e.g., methyl, ethyl, 1-propyl, 2-propyl, pentyl, and the like.
xe2x80x9cAlkylenexe2x80x9d means a linear saturated divalent hydrocarbon radical having from one to about twelve carbon atoms or a branched saturated divalent hydrocarbon radical having from three to about twelve carbon atoms, e.g., methylene, ethylene, propylene, 2-methylpropylene, pentylene, hexylene, and the like.
xe2x80x9cAralkylenexe2x80x9d means an alkylene radical defined above with an aromatic group attached to the alkylene radical, e.g., benzyl, pyridylmethyl, 1-naphthylethyl, and the like.
xe2x80x9cCured chemical compositionxe2x80x9d means that the chemical composition is dried or solvent has evaporated from the chemical composition at approximately ambient temperature (15-35xc2x0 C.) until dryness, up to approximately 24 hours.
xe2x80x9cFibrous substratexe2x80x9d means a material comprised of synthetic fibers such as wovens, knits, nonwovens, carpets, and other textiles; and a material comprised of natural fibers such as cotton, paper, and leather.
xe2x80x9cFluorocarbon monoalcoholxe2x80x9d means a compound having one hydroxyl group and a perfluoroalkyl or a perfluoroheteralkyl group, e.g., C4F9SO2N(CH3)CH2CH2OH, C4F9CH2CH2OH, C2F5O(C2F4O)3CF2CONHC2H4OH, c-C6F11CH2OH, and the like.
xe2x80x9cHaloxe2x80x9d means fluoro, chloro, bromo, or iodo, preferably fluoro and chloro.
xe2x80x9cHard substratexe2x80x9d means any rigid material that maintains its shape, e.g., glass, ceramic, concrete, natural stone, wood, metals, plastics, and the like.
xe2x80x9cHeteroacyloxyxe2x80x9d has essentially the meaning given above for acyloxy except that one or more heteroatoms (i.e. oxygen, sulfur, and/or nitrogen) may be present in the R group and the total number of carbon atoms present may be up to 50, e.g., CH3CH2OCH2CH2C(O)Oxe2x80x94, C4H9OCH2CH2OCH2CH2C(O)Oxe2x80x94, CH3O(CH2CH2O)nCH2CH2C(O)Oxe2x80x94, and the like.
xe2x80x9cHeteroalkoxyxe2x80x9d has essentially the meaning given above for alkoxy except that one or more heteroatoms (i.e. oxygen, sulfur, and/or nitrogen) may be present in the alkyl chain and the total number of carbon atoms present may be up to 50, e.g., CH3CH2OCH2CH2Oxe2x80x94, C4H9OCH2CH2OCH2CH2Oxe2x80x94, CH3O(CH2CH2O)nH, and the like.
xe2x80x9cHeteroalkylxe2x80x9d has essentially the meaning given above for alkyl except that one or more heteroatoms (i.e. oxygen, sulfur, and/or nitrogen) may be present in the alkyl chain, these heteroatoms being separated from each other by at least one carbon, e.g., CH3CH2OCH2CH2xe2x80x94, CH3CH2OCH2CH2OCH(CH3)CH2xe2x80x94, C4F9CH2CH2SCH2CH2xe2x80x94, and the like.
xe2x80x9cHeteroalkylenexe2x80x9d has essentially the meaning given above for alkylene except that one or more heteroatoms (i.e. oxygen, sulfur, and/or nitrogen) may be present in the alkylene chain, these heteroatoms being separated from each other by at least one carbon, e.g, xe2x80x94CH2OCH2Oxe2x80x94, xe2x80x94CH2CH2OCH2CH2xe2x80x94, xe2x80x94CH2CH2N(CH3)CH2CH2xe2x80x94, xe2x80x94CH2CH2SCH2CH2xe2x80x94, and the like.
xe2x80x9cHeteroaralkylenexe2x80x9d means an aralkylene radical defined above except that catenated oxygen, sulfur, and/or nitrogen atoms may be present, e.g., phenyleneoxymethyl, phenyleneoxyethyl, benzyleneoxymethyl, and the like.
xe2x80x9cLong-chain hydrocarbon monoalcoholxe2x80x9d means a compound having one hydroxyl group and a long chain hydrocarbon group having 10 to 18 carbons which may be saturated, unsaturated, or aromatic, and may optionally be substituted with one or more chlorine, bromine, trifluoromethyl, or phenyl groups, e.g., CH3(CH2)10CH2OH, CH3(CH2)14CH2OH, and the like.
xe2x80x9cOligomerxe2x80x9d means a polymer molecule consisting of only a few (for example, from 2 to about 20) repeat (polymerized) units.
xe2x80x9cPerfluoroalkylxe2x80x9d has essentially the meaning given above for xe2x80x9calkylxe2x80x9d except that all or essentially all of the hydrogen atoms of the alkyl radical are replaced by fluorine atoms and the number of carbon atoms is from 3 to about 8, e.g., perfluoropropyl, perfluorobutyl, perfluorooctyl, and the like.
xe2x80x9cPerfluoroalkylenexe2x80x9d has essentially the meaning given above for xe2x80x9calkylenexe2x80x9d except that all or essentially all of the hydrogen atoms of the alkylene radical are replaced by fluorine atoms, e.g., perfluoropropylene, perfluorobutylene, perfluorooctylene, and the like.
xe2x80x9cPerfluoroheteroalkylxe2x80x9d has essentially the meaning given above for xe2x80x9cheteroalkylxe2x80x9d except that all or essentially all of the hydrogen atoms of the heteroalkyl radical are replaced by fluorine atoms and the number of carbon atoms is from 3 to about 100, e.g., CF3CF2OCF2CF2xe2x80x94, CF3CF2O(CF2CF2O)3CF2CF2xe2x80x94, C3F7O(CF(CF3)CF2O)mCF(CF3)CF2xe2x80x94where m is from about 10 to about 30, and the like.
xe2x80x9cPerfluoroheteroalkylenexe2x80x9d has essentially the meaning given above for xe2x80x9cheteroalkylenexe2x80x9d except that all or essentially all of the hydrogen atoms of the heteroalkylene radical are replaced by fluorine atoms, and the number of carbon atoms is from 3 to about 100, e.g., xe2x80x94CF2OCF2xe2x80x94, xe2x80x94CF2O(CF2O)n(CF2CF2O)mCF2xe2x80x94, and the like.
xe2x80x9cPerfluorinated groupxe2x80x9d means an organic group wherein all or essentially all of the carbon bonded hydrogen atoms are replaced with fluorine atoms, e.g., perfluoroalkyl, perfluoroheteroalkyl, and the like.
xe2x80x9cPolyfunctional isocyanate compoundxe2x80x9d means a compound containing two or more isocyanate radicals, xe2x80x94NCO, attached to a multi-valent organic group, e.g., hexamethylene diisocyanate, the biuret and iscyanurate of hexamethylene diisocyanate, and the like.
xe2x80x9cPolyolxe2x80x9d means an organic compound or polymer with an average of at least about 2 primary or secondary hydroxyl groups per molecule, e.g., ethylene glycol, propylene glycol, 1,6-hexanediol, and the like.
xe2x80x9cPorousxe2x80x9d means capable of imbibing a liquid.
xe2x80x9cPolyalkylsiloxane diolxe2x80x9d means a molecule having two hydroxyl groups and a repeating unit with the structure, xe2x80x94(Si(R)2O)xe2x80x94, e.g., HOR[Si(CH3)2O]nSiROH, wherein each R is independently straight- or branched-chain alkyl.
xe2x80x9cPolyarylsiloxane diolxe2x80x9d means a molecule having two hydroxyl groups and a repeating unit with the structure, xe2x80x94(Si(Ar)2O)xe2x80x94, e.g., HOR[Si(C6H5)2O]SiROH, wherein each R is independently straight- or branched-chain alkyl.
xe2x80x9cRepellencyxe2x80x9d is a measure of a treated substrate""s resistance to wetting by oil and/or water and/or adhesion of particulate soil. Repellency may be measured by the test methods described herein.
xe2x80x9cResistance,xe2x80x9d in the context of soiling or staining, is a measure of the treated substrate""s ability to avoid staining and/or soiling when contacted by stain or soil respectively.
xe2x80x9cReleasexe2x80x9d is a measure of the treated substrate""s ability to have soil and/or stain removed by cleaning or laundering.
xe2x80x9cSilane groupxe2x80x9d means a group comprising silicon to which at least one hydrolyzable group is bonded, e.g., xe2x80x94Si(OCH3)3, xe2x80x94Si(OOCCH3)2CH3, xe2x80x94Si(Cl)3, and the like.
The chemical compositions of the present invention comprise one or more urethane oligomers having at least two repeating units selected from the group consisting of fluorine-containing urethane oligomers and long-chain hydrocarbon-containing urethane oligomers. This oligomer comprises the reaction product of (a) one or more polyfunctional isocyanate compounds; (b) one or more polyols; (c) one or more monoalcohols selected from the group consisting of fluorochemical monoalcohols, optionally substituted long-chain hydrocarbon monoalcohols, and mixtures thereof; (d) one or more silanes; and optionally (e) one or more water-solubilizing compounds comprising one or more water-solubilizing groups and at least one isocyanate-reactive hydrogen containing group.
The silanes are of the following formula (I):
Xxe2x80x94R1xe2x80x94Sixe2x80x94(Y)3xe2x80x83xe2x80x83formula (I)
wherein:
X is xe2x80x94NH2; xe2x80x94SH; xe2x80x94OH; xe2x80x94Nxe2x95x90Cxe2x95x90O; or xe2x80x94NRH where R is a phenyl, straight or branched aliphatic, alicyclic, or aliphatic ester group;
R1 is an alkylene, heteroalkylene, aralkylene, or heteroaralkylene group; and
each Y is independently a hydroxyl; a hydrolyzable moiety selected from the group consisting of alkoxy, acyloxy, heteroalkyoxy, heteroacyloxy, halo, and oxime; or a non-hydrolyzable moiety selected from the group consisting of phenyl, alicyclic, straight-chain aliphatic, and branched-chain aliphatic, wherein at least one Y is a hydrolyzable moiety.
The oligomer comprises at least two repeating (polymerized) units. Each repeating unit comprises a urethane group that is derived or derivable from the reaction of at least one polyfunctional isocyanate compound and at least one polyol. The oligomer is terminated with (i) one or more perfluoroalkyl groups, one or more perfluoroheteroalkyl groups, or one or more long-chain hydrocarbyl groups; and (ii) one or more silyl groups. The oligomer can further comprise one or more water-solubilizing groups, these solubilizing groups independently being pendant from the repeating unit or terminal. The oligomer also can further comprise one or more fluorine-containing groups pendant from the repeating unit, these fluorine-containing groups independently being perfluoroalkyl or perfluoroheteroalkyl groups. Additionally, the oligomer can comprise one or more perfluoroheteroalkylene groups within the backbone of the repeating unit.
In one preferred embodiment, the composition of the present invention comprises a mixture of urethane molecules arising from the reaction of (a) one or more polyfunctional isocyanate compounds, (b) one or more polyols, (c) one or more fluorochemical monoalcohols, and (d) one or more silanes as described above.
In another preferred embodiment, the composition of the present invention comprises a mixture of urethane molecules arising from the reaction of (a) one or more polyfunctional isocyanate compounds, (b) one or more polyols, (c) one or more fluorochemical monoalcohols, (d) one or more silanes as described above, and (e) one or more water-solubilizing compounds comprising one or more water-solubilizing groups and at least one isocyanate-reactive hydrogen containing group. The water-solubilizing compounds of the present invention can be represented in general by xe2x80x9cW-H,xe2x80x9d wherein W represents the residue of the water-solubilizing compound comprising one or more water-solubilizing groups and H represents the active hydrogen(s).
In a further preferred embodiment, the composition of the present invention comprises a mixture of urethane molecules arising from the reaction of (a) one or more polyfunctional isocyanate compounds, (b) one or more polyols, (c) one or more optionally substituted long-chain hydrocarbon monoalcohols, (d) one or more silanes as described above, and (e) one or more water-solubilizing compounds comprising one or more water-solubilizing groups and at least one isocyanate-reactive hydrogen containing group.
The composition can further contain fluorine-containing and or long-chain hydrocarbon-containing urethane compounds having fewer than two repeating or repeatable units. The mixture of urethane molecules preferably comprises urethane molecules having a varying number of repeating units, including zero, one, two, and more repeating units. This mixture of urethane molecules comprising a varying number of repeating units allows simple blending of the above components in preparing the fluorochemical composition.
Preferred classes of urethane oligomers that may be present are represented by the following formulas (III) through (VI):
RfZR2xe2x80x94O(xe2x80x94CONHxe2x80x94Q(A)mxe2x80x94NHCOxe2x80x94OR3Oxe2x80x94)nCONHxe2x80x94Q(A)xe2x80x94NHCOxe2x80x94Xxe2x80x2R1Si(Y)3xe2x80x83xe2x80x83(III)
RfZR2xe2x80x94O(xe2x80x94CONHxe2x80x94Q(A)mxe2x80x94NHCOxe2x80x94OR3Oxe2x80x94)nCONHR1Si(Y)3xe2x80x83xe2x80x83(IV)
R4xe2x80x94O(xe2x80x94CONHxe2x80x94Q(A)mxe2x80x94NHCOxe2x80x94OR3Oxe2x80x94)nCONHxe2x80x94Q(A)xe2x80x94NHCOxe2x80x94Xxe2x80x2R1Si(Y)3xe2x80x83xe2x80x83(V)
R4xe2x80x94O(xe2x80x94CONHxe2x80x94Q(A)mxe2x80x94NHCOxe2x80x94OR3Oxe2x80x94)nCONHR1Si(Y)3xe2x80x83xe2x80x83(VI)
wherein:
RfZR2xe2x80x94 is a residue of at least one of the fluorochemical monoalcohols;
Rf is a perfluoroalkyl group having 3 to about 8 carbon atoms, or a perfluoroheteroalkyl group having 3 to about 50 carbon atoms;
Z is a covalent bond, sulfonamido (xe2x80x94SO2NRxe2x80x94), or carboxamido (xe2x80x94CONRxe2x80x94) where R is hydrogen or alkyl;
R1 is an alkylene, heteroalkylene, aralkylene, or heteroaralkylene group;
R2 is a divalent straight- or branched-chain alkylene, cycloalkylene, or heteroalkylene group of 1 to 14 carbon atoms, preferably 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms, and most preferably two carbon atoms, and preferably R2 is alkylene or heteroalkylene of 1 to 14 carbon atoms;
Q is a multi-valent organic group which is a residue of the polyfunctional isocyanate compound;
R3 is a divalent organic group which is a residue of the polyol and may be substituted with or contain (i) water-solubilizing groups selected from the group consisting of carboxylate, sulfate, sulfonate, phosphonate, ammonium, quaternary ammonium, and mixtures thereof and (ii) perfluorinated groups;
Xxe2x80x2 is xe2x80x94Oxe2x80x94, xe2x80x94Sxe2x80x94, or xe2x80x94N(R)xe2x80x94, wherein R is hydrogen or alkyl;
R4 is an optionally substituted long-chain hydrocarbon derived from the long-chain hydrocarbon monoalcohol;
each Y is independently a hydroxy; a hydrolyzable moiety selected from the group consisting of alkoxy, acyloxy, heteroalkoxy, heteroacyloxy, halo, and oxime; or a non-hydrolyzable moiety selected from the group consisting of phenyl, alicyclic, straight-chain aliphatic, and branched-chain aliphatic, wherein at least one Y is a hydrolyzable moiety.
A is selected from the group consisting of RfZR2xe2x80x94OCONHxe2x80x94, (Y)3SiR1XCONHxe2x80x94, (Y)3SiR1NHCOOR3OCONHxe2x80x94, and Wxe2x80x94CONHxe2x80x94, wherein W is a residue of the water-solubilizing compound comprising one or more water-solubilizing groups;
m is an integer from 0 to 2; and
n, which is the number of repeating units, is an integer from 2 to 10.
Polyfunctional isocyanate compounds useful in the present invention comprise isocyanate radicals attached to the multi-valent organic group, Q, which can comprise a multi-valent aliphatic, alicyclic, or aromatic moiety; or a multi-valent aliphatic, alicyclic or aromatic moiety attached to a biuret, an isocyanurate, or a uretdione, or mixtures a, thereof. Preferred polyfunctional isocyanate compounds contain two or three xe2x80x94NCO radicals. Compounds containing two xe2x80x94NCO radicals are comprised of divalent aliphatic, alicyclic, araliphatic, or aromatic moieties to which the xe2x80x94NCO radicals are attached. Preferred compounds containing three xe2x80x94NCO radicals are comprised of isocyanatoaliphatic, isocyanatoalicyclic, or isocyanatoaromatic, monovalent moieties, which are attached to a biuret or an isocyanurate.
Representative examples of suitable polyfunctional isocyanate compounds include isocyanate functional derivatives of the polyfunctional isocyanate compounds as defined herein. Examples of derivatives include, but are not limited to, those selected from the group consisting of ureas, biurets, allophanates, dimers and trimers (such as uretdiones and isocyanurates) of isocyanate compounds, and mixtures thereof. Any suitable organic polyisocyanate, such as an aliphatic, alicyclic, araliphatic, or aromatic polyisocyanate, may be used either singly or in mixtures of two or more. The aliphatic polyfunctional isocyanate compounds generally provide better light stability than the aromatic compounds. Aromatic polyfunctional isocyanate compounds, on the other hand, are generally more economical and reactive toward polyols and other poly(active hydrogen) compounds than are aliphatic polyfunctional isocyanate compounds. Suitable aromatic polyfunctional isocyanate compounds include, but are not limited to, those selected from the group consisting of 2,4-toluene diisocyanate (TDI), 2,6-toluene diisocyanate, an adduct of TDI with trimethylolpropane (available as DESMODUR(trademark) CB from Bayer Corporation, Pittsburgh, Pa.), the isocyanurate trimer of TDI (available as DESMODUR(trademark) IL from Bayer Corporation, Pittsburgh, Pa.), diphenylmethane 4,4xe2x80x2-diisocyanate (MDI), diphenylmethane 2,4xe2x80x2-diisocyanate, 1,5-diisocyanato-naphthalene, 1,4-phenylene diisocyanate, 1,3-phenylene diisocyanate, 1-methyoxy-2,4-phenylene diisocyanate, 1-chlorophenyl-2,4-diisocyanate, and mixtures thereof.
Examples of useful aiicyclic polyfunctional isocyanate compounds include, but are not limited to, those selected from the group consisting of dicyclohexylmethane diisocyanate (H12MDI, commercially available as DESMODUR(trademark) W, available from Bayer Corporation, Pittsburgh, Pa.), 4,4xe2x80x2-isopropyl-bis(cyclohexylisocyanate), isophorone diisocyanate (IPDI), cyclobutane-1,3-diisocyanate, cyclohexane 1,3-diisocyanate, cyclohexane 1,4-diisocyanate (CHDI), 1,4-cyclohexanebis(methylene isocyanate) (BDI), 1,3-bis(isocyanatomethyl)cyclohexane (H6XDI), 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, and mixtures thereof.
Examples of useful aliphatic polyfunctional isocyanate compounds include, but are not limited to, those selected from the group consisting of 1,4-tetramethylene diisocyanate, hexamethylene 1,4-diisocyanate, hexamethylene 1,6-diisocyanate (HDI), 1,12-dodecane diisocyanate, 2,2,4-trimethyl-hexamethylene diisocyanate (TMDI), 2,4,4-trimethyl-hexamethylene diisocyanate ((trademark)DI), 2-methyl-1,5-pentamethylene diisocyanate, dimer diisocyanate, the urea of hexamethylene diisocyanate, the biuret of hexamethylene 1,6-diisocyanate (HDI) (available as DESMODUR(trademark) N-100 and N-3200 from Bayer Corporation, Pittsburgh, Pa.), the isocyanurate of HDI (available as DESMODUR(trademark) N-3300 and DESMODUR(trademark) N-3600 from Bayer Corporation, Pittsburgh, Pa.), a blend of the isocyanurate of HDI and the uretdione of HDI (available as DESMODUR(trademark) N-3400 available from Bayer Corporation, Pittsburgh, Pa.), and mixtures thereof.
Examples of useful araliphatic polyisocyanates include, but are not limited to, those selected from the group consisting of m-tetramethyl xylylene diisocyanate (m-TMXDI), p-tetramethyl xylylene diisocyanate (p-TMXDI), 1,4-xylylene diisocyanate (XDI), 1,3-xylylene diisocyanate, p-(1-isocyanatoethyl)-phenyl isocyanate, m-(3-isocyanatobutyl)-phenyl isocyanate, 4-(2-isocyanatocyclohexyl-methyl)-phenyl isocyanate, and mixtures thereof.
Preferred polyisocyanates, in general, include those selected from the group consisting of hexamethylene 1,6-diisocyanate (HDI), 1,12-dodecane diisocyanate isophorone diisocyanate, toluene diisocyanate, dicyclohexylmethane 4,4xe2x80x2diisocyanate, MDI, derivatives of all the aforementioned, including DESMODUR(trademark) N-100, N-3200, N-3300, N-3400, N-3600, and mixtures thereof.
Suitable commercially available polyfunctional isocyanates are exemplified by DESMODUR(trademark) N-3200, DESMODUR(trademark) N-3300, DESMODUR(trademark) N-3400, DESMODUR(trademark) N-3600, DESMODUR(trademark) H (HDI), DESMODUR(trademark) W (bis[4-isocyanatocyclohexyl]methane), MONDUR(trademark) M (4,4xe2x80x2-diisocyanatodiphenylmethane), MONDUR(trademark) TDS (98% toluene 2,4-diisocyanate), MONDUR(trademark) TD-80 (a mixture of 80% 2,4 and 20% 2,6-toluene diisocyanate isomers), and DESMODUR(trademark) N-100, each available from Bayer Corporation, Pittsburgh, Pa.
Other useful triisocyanates are those obtained by reacting three moles of a diisocyanate with one mole of a triol. For example, toluene diisocyanate, 3-isocyanatomethyl-3,4,4-trimethylcyclohexyl isocyanate, or m-tetramethylxylene diisocyanate can be reacted with 1,1,1-tris(hydroxymethyl)propane to form triisocyanates. The product from the reaction with m-tetramethylxylene diisocyanate is commercially available as CYTHANE(trademark) 3160 (American Cyanamid, Stamford, Conn.).
Polyols suitable for use in preparing the chemical compositions of the present invention include those organic polyols that have an average hydroxyl functionality of at least about 2 (preferably, about 2 to 5; more preferably, about 2 to 3; most preferably, about 2, as diols are most preferred). The hydroxyl groups can be primary or secondary, with primary hydroxyl groups being preferred for their greater reactivity. Mixtures of diols with polyols that have an average hydroxyl functionality of about 2.5 to 5 (preferably about 3 to 4; more preferably, about 3) can also be used. It is preferred that such mixtures contain no more than about 20 percent by weight of such polyols, more preferably no more than about 10 percent, and most preferably no more than about 5 percent. Preferred mixtures are mixtures of diols and triols.
Suitable polyols include those that comprise at least one aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aromatic, heteroaromatic, or polymeric moiety. Preferred polyols are aliphatic or polymeric polyols that contain hydroxyl groups as terminal groups or as groups that are pendant from the backbone chain of the polyol.
The molecular weight (that is, the number average molecular weight) of hydrocarbon polyols can generally vary from about 60 to about 2000, preferably, from about 60 to about 1000, more preferably, from about 60 to about 500, most preferably, from about 60 to about 300. The equivalent weight (that is, the number average equivalent weight) of hydrocarbon polyols generally can be in the range of about 30 to about 1000, preferably, from about 30 to about 500, more preferably, from about 30 to about 250. Polyols of higher equivalent weight can have a tendency to reduce the stain-release properties provided by the chemical compositions of the present invention unless the polyol contains an Rf group or the polyol comprises a perfluoropolyether. If the polyol comprises a perfluoropolyether, it can have a molecular weight as high as approximately 7000 and can still provide adequate stain-release properties.
When the polyols of the present invention are diols, the diols can be substituted with or contain other groups. Thus, a preferred diol is selected from the group consisting of a branched- or straight-chain hydrocarbon diol, a diol containing at least one solubilizing group, a fluorinated diol comprising a monovalent or divalent perfluorinated group, a diol comprising a silane group, a polyalkylsiloxane diol, a polyarylsiloxane diol, and mixtures thereof. Solubilizing groups include carboxylate, sulfate, sulfonate, phosphate, phosphonate, ammonium, quaternary ammonium, and the like.
Perfluorinated monovalent groups (Rf) may be perfluoroalkyl and perfluoroheteroalkyl, and perfluorinated divalent groups may be perfluoroalkylene and perfluoroheteroalkylene. Perfluoroalkyl groups are preferred, with perfluoroalkyl groups having from 2 to 6 carbon atoms being more preferred and perfluoroalkyl groups having 4 carbon atoms being most preferred. Another embodiment comprises perfluoroheteroalkyl groups having 6 to 50 carbon atoms. Perfluorinated divalent groups are preferably perfluoroheteroalkylene groups. Perfluoroheteroalkylene groups are preferably perfluoropolyether groups having from about 3 to about 50 carbon atoms.
The silane groups of the diol may contain one, two, or three hydrolyzable groups on the silicon atom. Hydrolyzable groups are as defined below. Polyalkylsiloxane diols include, but are not limited to, hydroxyalkyl terminated polydimethyl siloxanes, polymethyloctadecylsiloxane, polydimethylmethyloctadecylsiloxane, polydimethyldodecyltetradecylsiloxane, polymethylhexadecylsiloxane, polymethyloctylsiloxane, polymethyl-3,3,3-trifluoropropylsiloxane, and the like. Polyarylsiloxane diols are essentially the same as the polyalkylsiloxanes with some or all of the methyl groups replaced with phenyl groups, such as hydroxyalkyl terminated polydiphenylsiloxane and hydroxyalkyl terminated dimethyl-diphenylsiloxane copolymer.
Representative examples of suitable non-polymeric polyols include alkylene glycols, polyhydroxyalkanes, and other polyhydroxy compounds. The alkylene glycols include, for example, 1,2-ethanediol; 1,2-propanediol; 3-chloro-1,2-propanediol; 1,3-propanediol; 1,3-butanediol; 1,4-butanediol; 2-methyl-1,3-propanediol; 2,2-dimethyl-1,3-propanediol (neopentylglycol); 2-ethyl-1,3-propanediol; 2,2-diethyl-1,3-propanediol; 1,5-pentanediol; 2-ethyl- 1,3-pentanediol; 2,2,4-trimethyl- 1,3-pentanediol; 3-methyl-1,5-pentanediol; 1,2-, 1,5-, and 1,6-hexanediol; 2-ethyl-1,6-hexanediol; bis(hydroxymethyl)cyclohexane; 1,8-octanediol; bicyclo-octanediol; 1,10-decanediol; tricyclo-decanediol; norbomanediol; and 1,18-dihydroxyoctadecane.
The polyhydroxyalkanes include, for example, glycerine; trimethylolethane; trimethylolpropane; 2-ethyl-2-(hydroxymethyl)-1,3-propanediol; 1,2,6-hexanetriol; pentaerythritol; quinitol; mannitol; and sorbitol.
The other polyhydroxy compounds include, for example, such as di(ethylene glycol); tri(ethylene glycol); tetra(ethylene glycol); tetramethylene glycol; dipropylene glycol; diisopropylene glycol; tripropylene glycol; bis(hydroxymethyl)propionic acid; N,N-bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane; bicine; N-bis(2-hydroxyethyl) perfluorobutylsulfonamide; 1,11-(3,6-dioxaundecane)diol; 1,14-(3,6,9,12-tetraoxatetradecane)diol; 1,8-(3,6-dioxa-2,5,8-trimethyloctane)diol; 1,14-(5,10-dioxatetradecane)diol; castor oil; 2-butyne-1,4-diol; N,N-bis(hydroxyethyl)benzamide; 4,4xe2x80x2-bis(hydroxymethyl)diphenylsulfone; 1,4-benzenedimethanol; 1,3-bis(2-hydroxyethyoxy)benzene; 1,2-dihydroxybenzene; resorcinol; 1,4-dihydroxybenzene; 3,5-, 2,6-, 2,5-, and 2,4-dihydroxybenzoic acid; 1,6-, 2,6-, 2,5-, and 2,7-dihydroxynaphthalene; 2,2xe2x80x2- and 4,4xe2x80x2-biphenol; 1,8-dihydroxybiphenyl; 2,4-dihydroxy-6-methyl-pyrimidine; 4,6-dihydroxypyrimidine; 3,6-dihydroxypyridazine; bisphenol A; 4,4xe2x80x2-ethylidenebisphenol; 4,4xe2x80x2-isopropylidenebis(2,6-dimethylphenol); bis(4-hydroxyphenyl)methane; 1,1-bis(4-hydroxyphenyl)-1-phenylethane (bisphenol C); 1,4-bis(2-hydroxyethyl)piperazine; bis(4-hydroxyphenyl) ether; 1,4-bis(1-hydroxy-1,1-dihydroperfluoroethoxyethoxy) perfluoro-n-butane (HOCH2CF2OC2F4O(CF2)4OC2F4OCF2CH2OH); 1,4-bis( 1-hydroxy-1,1-dihydroperfluoropropoxy) perfluoro-n-butane (HOCH2CF2CF2O(CF2)4OCF2CF2CH2OH); as well as other aliphatic, heteroaliphatic, saturated alicyclic, aromatic, saturated heteroalicyclic, and heteroaromatic polyols; and the like, and mixtures thereof.
Representative examples of useful polymeric polyols include polyoxyethylene, polyoxypropylene, and ethylene oxide-terminated polypropylene glycols and triols of molecular weights from about 200 to about 2000, corresponding to equivalent weights of about 100 to about 1000 for the diols or about 70 to about 700 for triols; polytetramethylene glycols of varying molecular weight; polydialkylsiloxane diols of varying molecular weight; hydroxy-terminated polyesters and hydroxy-terminated polylactones (e.g., polycaprolactone polyols); hydroxy-terminated polyalkadienes (e.g., hydroxyl-terminated polybutadienes); and the like. Mixtures of polymeric polyols can be used if desired.
Useful commercially available polymeric polyols include CARBOWAX(trademark) poly(ethylene glycol) materials in the number average molecular weight (Mn) range of from about 200 to about 2000 (available from Union Carbide Corp., Danbury, Conn.); poly(propylene glycol) materials such as PPG-425 (available from Lyondell Chemical Company, Houston, Tex.); block copolymers of poly(ethylene glycol) and poly(propylene glycol) such as PLURONIC(trademark) L31 (available from BASF Corporation, Mount Olive, N.J.); fluorinated oxetane polyols made by the ring-opening polymerization of fluorinated oxetane such as POLY-3-FOX(trademark) (available from Omnova Solutions, Inc., Akron Ohio); polyetheralcohols prepared by ring opening addition polymerization of a fluorinated organic group substituted epoxide with a compound containing at least two hydroxyl groups as described in U.S. Pat. No. 4,508,916 (Newell et al); perfluoropolyether diols such as FOMBLIN(trademark) ZDOL (HOCH2CF2O(CF2O)8-12(CF2CF2O)8-12CF2CH2OH, available from Ausimont, Inc., Thorofare, N.J.); Bisphenol A ethoxylate, Bisphenol A propyloxylate, and Bisphenol A propoxylate/ethoxylate (available from Sigma-Aldrich, Milwaukee, Wis.); polytetramethylene ether glycols such as POLYMEG(trademark) 650 and 1000 (available from Quaker Oats Company, Chicago, Ill.) and the TERATHANE(trademark) polyols (available from E.I. duPont de Nemours, Wilmington, Del.); hydroxyl-terminated polybutadiene resins such as the POLY BD(trademark) materials (available from Elf Atochem, Philadelphia, Pa.); the xe2x80x9cPePxe2x80x9d series (available from Wyandotte Chemicals Corporation, Wyandotte, Mich.) of polyoxyalkylene tetrols having secondary hydroxyl groups, for example, xe2x80x9cPePxe2x80x9d 450, 550, and 650; polycaprolactone polyols with Mn in the range of about 200 to about 2000 such as TONE(trademark) 0201, 0210, 0301, and 0310 (available from Union Carbide Corp., Danbury, Conn.); xe2x80x9cPARAPLEX(trademark) U-148xe2x80x9d(available from Rohm and Haas Co., Philadelphia, Pa.), an aliphatic polyester diol; polyester polyols such as the MULTRON(trademark) poly(ethyleneadipate)polyols (available from Mobay Chemical Corp., Irvine, Calif.); polycarbonate diols such as DURACARB(trademark) 120, a hexanediol carbonate with Mn=900 (available from PPG Industries, Inc., Pittsburgh, Pa.); and the like; and mixtures thereof.
Preferred polyols include 2,2-bis(hydroxymethyl)propionic acid; N,N-bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane; bicine; 3,5-dihydroxybenzoic acid; 2,4-dihydroxybenzoic acid; N-bis(2-hydroxyethyl)perfluorobutyl sul fonamide; 1,2-ethanediol; 1,2- and 1,3-propanediol; 1,3- and 1,4-butanediol; neopentylglycol; 1,5-pentanediol; 3-methyl-1,5-pentanediol; 1,2-, 1,5-, and 1,6-hexanediol; bis(hydroxymethyl)cyclohexane; 1,8-octanediol; 1,10-decanediol; di(ethylene glycol); tri(ethylene glycol); tetra(ethylene glycol); di(propylene glycol); di(isopropylene glycol); tri(propylene glycol); poly(ethylene glycol) diols (number average molecular weight of about 200 to about 1500); poly(di(ethylene glycol) phthalate) diol (having number average molecular weights of, for example, about 350 or about 575); poly(propylene glycols) diols (number average molecular weight of about 200 to about 500); block copolymers of poly(ethylene glycol) and poly(propylene glycol) such as PLURONIC(trademark) L31 (available from BASF Corporation, Mount Olive, N.J.); polydimethylsiloxane diol; fluorinated oxetane polyols made by the ring-opening polymerization of fluorinated oxetane such as POLY-3-FOX(trademark) (available from Omnova Solutions, Inc., Akron Ohio); polyetheralcohols prepared by ring opening addition polymerization of a fluorinated organic group substituted epoxide with a compound containing at least two hydroxyl groups as described in U.S. Pat. No. 4,508,916 (Newell et al); perfluoropolyether diols such as FOMBLIN(trademark) ZDOL (HOCH2CF2O(CF2O)8-12(CF2CF2O)8-12CF2CH2OH, available from Ausimont, Inc., Thorofare, N.J.); 1,4-bis(1-hydroxy-1,1-dihydroperfluoroethoxyethoxy)perfluoro-n-butane (HOCH2CF2OC2F4O(CF2)4OC2F4OCF2CH2OH); 1,4-bis (1-hydroxy-1,1-dihydroperfluoropropoxy)perfluoro-n-butane (HOCH2CF2CF2O(CF2)4OCF2CF2CH2OH); polycaprolactone diols (number average molecular weight of about 200 to about 600); resorcinol; hydroquinone; 1,6-, 2,5-, 2,6-, and 2,7-dihydroxynaphthalene; 4,4xe2x80x2-biphenol; bisphenol A; bis(4-hydroxyphenyl)methane; and the like; and mixtures thereof.
More preferred polyols include bis(hydroxymethyl)propionic acid; bicine; N-bis(2-hydroxyethyl)perfluorobutylsulfonamide; 1,2-ethanediol; 1,2- and 1,3-propanediol; 1,4-butanediol; neopentylglycol; 1,2- and 1,6-hexanediol; di(ethylene glycol); tri(ethylene glycol); 1,4-bis(1-hydroxy-1,1-dihydroperfluoropropoxy)perfluoro-n-butane (HOCH2CF2CF2O(CF2)4OCF2CF2CH2OH); fluorinated oxetane polyols made by the ring-opening polymerization of fluorinated oxetane such as POLY-3-FOX(trademark) (available from Omnova Solutions, Inc., Akron Ohio); poly(di(ethylene glycol) phthalate) diol (having number average molecular weights of, for example, about 350 or about 575); poly(ethylene glycol) diols (having number average molecular weights of, for example, about 200, 300, 400); polydimethylsiloxane diol; polypropylene glycol (having a number average molecular weight of, for example, about 425); dimer diol; polycaprolactone diol (having a number average molecular weight of, for example, about 530); 3,5-dihydroxybenzene; bisphenol A; resorcinol; hydroquinone; and mixtures thereof.
Fluorochemical monoalcohols suitable for use in preparing the chemical compositions of the present invention include those that comprise at least one Rf group. The Rf groups can contain straight-chain, branched-chain, or cyclic fluorinated alkylene groups or any combination thereof. The Rf groups can optionally contain one or more heteroatoms (i.e. oxygen, sulfur, and/or nitrogen) in the carbon-carbon chain so as to form a carbon-heteroatom-carbon chain (i.e. a heteroalkylene group). Fully-fluorinated groups are generally preferred, but hydrogen or chlorine atoms can also be present as substituents, provided that no more than one atom of either is present for every two carbon atoms. It is additionally preferred that any Rf group contain at least about 40% fluorine by weight, more preferably at least about 50% fluorine by weight. The terminal portion of the group is generally fully-fluorinated, preferably containing at least three fluorine atoms, e.g., CF3Oxe2x80x94, CF3CF2xe2x80x94, CF3CF2CF2xe2x80x94, (CF3)2 CFxe2x80x94, SF5CF2xe2x80x94. Perfluorinated aliphatic groups (i.e., those of the formula CnF2n+1xe2x80x94) wherein n is 2 to 6 inclusive are the preferred Rf groups, with n=3 to 5 being more preferred and with n=4 being the most preferred.
Useful fluorine-containing monoalcohols include compounds of the following formula II:
Rfxe2x80x94Zxe2x80x94Rxe2x80x94OHxe2x80x83xe2x80x83formula (II)
wherein:
Rf is a perfluoroalkyl group or a perfluoroheteroalkyl group as defined above;
Z is a connecting group selected from a covalent bond, a sulfonamido group, a carboxamido group, a carboxyl group, or a sulfinyl group; and
R2 is a divalent straight- or branched-chain alkylene, cycloalkylene, or heteroalkylene group of 1 to 14 carbon atoms, preferably 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms, and most preferably two carbon atoms. Representative examples of useful fluorine-containing monoalcohols include the following:
and the like, and mixtures thereof, wherein Rf is a perfluoroalkyl group of 2 to 16 carbon atoms. If desired, rather than using such alcohols, similar thiols can be utilized.
Preferred fluorine-containing monoalcohols include 2-(N-methylperfluoro butanesul fonamido)ethanol; 2-(N-ethylperfluorobutanesulfonam ido)ethanol; 2-(N-methylperfluorobutanesulfonamido)propanol; N-methyl-N-(4-hydroxybutyl)perfluorohexanesulfonamride; 1,1,2,2-tetrahydroperfluorooctanol; 1,1-; dihydroperfluorooctanol; C6F13CF(CF3)CO2C2H4CH(CH3)OH; n-C6F13CF(CF3)CON(H)CH2CH2OH; C4F9OC2F4OCF2CH2OCH2CH2OH; C3F7CON(H)CH2CH2OH; 1,1,2,2,3,3-hexahydroperfluorodecanol; C3F7O(CF(CF3)CF2O)1-36CF(CF3)CH2OH; CF3O(CF2CF2O)1-36CF2CH2OH; and the and mixtures thereof.
Long-chain hydrocarbon monoalcohols suitable for use in the chemical compositions of the present invention comprise at least one, essentially unbranched, hydrocarbon chain having from 10 to about 18 carbon atoms which may be saturated, unsaturated, or aromatic. These long-chain hydrocarbon monoalcohols can be optionally substituted, for example, with groups such as one or more chlorine, bromine, trifluoromethyl, or phenyl groups. Representative long-chain hydrocarbon monoalcohols include 1-octanol, 1-decanol, 1-dodecanol, 1-tetradecanol, 1-hexadecanol, 1-octadecanol, and the like, and mixtures thereof. Preferred long-chain hydrocarbon monoalcohols have 12 to 16 carbon atoms, with 12 to 14 carbon atoms being more preferred and 12 carbon atoms being most preferred for water solubility and performance.
Silane compounds suitable for use in the chemical compositions of the present invention are those of the following formula (I):
Xxe2x80x94R1xe2x80x94Sixe2x80x94(Y)3xe2x80x83xe2x80x83formula (I)
wherein X, R1, and Y are as defined previously. Therefore, these silane compounds contain one, two, or three hydrolyzable groups (Y) on the silicon and one organic group including an isocyanate-reactive or an active hydrogen reactive radical (Xxe2x80x94R1). Any of the conventional hydrolyzable groups, such as those selected from the group consisting of alkoxy, acyloxy, heteroalkoxy, heteroacyloxy, halo, oxime, and the like, can be used as the hydrolyzable group (Y). The hydrolyzable group (Y) is preferably alkoxy or acyloxy and more preferably alkoxy.
When Y is halo, the hydrogen halide liberated from the halogen-containing silane can cause polymer degradation when cellulose substrates are used. When Y is an oxime group, lower oxime groups of the formula xe2x80x94Nxe2x95x90CR5R6, wherein R5 and R6 are monovalent lower alkyl groups comprising about 1 to about 12 carbon atoms, which can be the same or different, preferably selected from the group consisting of methyl, ethyl, propyl, and butyl, are preferred.
Representative divalent bridging radicals (R1) include, but are not limited to, those selected from the group consisting of xe2x80x94CH2CH2xe2x80x94, xe2x80x94CH2CH2CH2xe2x80x94, xe2x80x94CH2CH2CH2OCH2CH2xe2x80x94, xe2x80x94CH2CH2C6H4CH2CH2xe2x80x94, and xe2x80x94CH2CH2O(C2H4O)2CH2CH2N(CH3)CH)CH2CH2CH2xe2x80x94.
Other preferred silane compounds are those which contain one or two hydrolyzable groups, such as those having the structures R2OSi(R7)2R1XH and (R8O)2Si(R7)R1XH, wherein R1 is as previously defined, and R7 and R8 are selected from the group consisting of a phenyl group, an alicycylic group, or a straight or branched aliphatic group having from about 1 to about 12 carbon atoms. Preferably, R7 and R8 are a lower alkyl group comprising 1 to 4 carbon atoms.
Following the hydrolysis of some of these terminal silyl groups, inter-reaction with a substrate surface comprising xe2x80x94SiOH groups or other metal hydroxide groups to form siloxane or metal-oxane linkages, e.g., 
can occur. Bonds thus formed, particularly Sixe2x80x94Oxe2x80x94Si bonds, are water resistant and can provide enhanced durability of the stain-release properties imparted by the chemical compositions of the present invention.
Such silane compounds are well known in the art and many are commercially available or are readily prepared. Representative isocyanate-reactive silane compounds include, but are not limited to, those selected from the group consisting of:
and mixtures thereof.
Representative examples of hydroxyl-reactive silane compounds include, but are not limited to, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and the like.
The chemical compositions of the present invention optionally may contain water-solubilizing compounds (W-H) comprising one or more water-solubilizing groups and at least one isocyanate-reactive hydrogen containing group. These water-solubilizing compounds include, for example, diols and monoalcohols comprising one or more water-solubilizing groups, added in addition to the one or more polyols and one or more monoalcohols as described above.
The solubilizing groups of the water-solubilizing compounds include, for example, carboxylate, sulfate, sulfonate, phosphate, phosphonate, ammonium, and quaternary ammonium groups. Such groups may be represented as xe2x80x94CO2M, xe2x80x94OSO3M, xe2x80x94O3M, xe2x80x94OPO3M, xe2x80x94PO(OM)2, xe2x80x94NR2HX, xe2x80x94NR3X, xe2x80x94NRH2X, and xe2x80x94NH3X, respectively, wherein M is H or one equivalent of a monovalent or divalent soluble cation such as sodium, potassium, calcium, and NR3H+; X is a soluble anion such as those selected from the group consisting of halide, hydroxide, carboxylate, sulfonates, and the like; and R is selected from the group consisting of a phenyl group, a cycloaliphatic group, or a straight or branched aliphatic group having from about 1 to about 12 carbon atoms. Preferably, R is a lower alkyl group having from 1 to 4 carbon atoms. The group xe2x80x94NR3X is a salt of a water-soluble acid, for example trimethyl ammonium chloride, pyridinium sulfate, etc. or an ammonium substituent. The group xe2x80x94NR2HX is the salt of a water-soluble acid, such as dimethyl ammonium acetate or propionate. The group xe2x80x94NRH2X is the salt of a water-soluble acid, such as methyl ammonium acetate or propionate. The group xe2x80x94NH3X is the salt of a water-soluble acid, such as ammonium acetate or propionate. The salt form can be made by simple neutralization of the acid group with a base such as an amine, a quaternary ammonium hydroxide, an alkali metal carbonate or hydroxide, or the like; or alternatively by simple reaction of the amino group with a carboxylic acid, a sulfonic acid, a halo acid, or the like. Carboxylic acid groups in salt form are preferred because they have been found to impart water solubility to the chemical compositions of the present invention without causing undue loss of the durable stain-release properties imparted by the chemical composition.
The isocyanate-reactive hydrogen containing group is selected from the group consisting of xe2x80x94OH, xe2x80x94SH, NH2, and NRH wherein R is selected from the group consisting of a phenyl group, a cycloaliphatic group, or a straight or branched aliphatic group having from about 1 to about 12 carbon atoms. Preferably, R is a lower alkyl group having from 1 to 4 carbon atoms. A representative suitable diol with a solubilizing group is 1,1-bis(hydroxymethyl)propionic acid and its salts such as its ammonium salt. A representative suitable monoalcohol with a solubilizing group is glycolic acid (HOCH2COOH) and its salts. The amount of water-solubilizing group should be sufficient to solubilize the chemical composition. Typically, the isocyanate: solubilizing group ratio should be from about 3:1 to about 16:1, preferably from about 5:1 to about 11:1. Illustrative water-solubilizing compounds having suitable water-solubilizing groups include, but are not limited to, those independently selected from the group consisting of HOCH2COOH; HSCH2COOH; (HOCH2CH2)2NCH2COOH; HOC(CO2H) (CH2CO2H)2; (H2N(CH2)nCH2)2NCH3 wherein n is an integer of 1 to 3; (HOCH2)2C(CH3)COOH; (HO(CH2)nCH2)2NCH3 wherein n is an integer of 1 to 3; HOCH2CH(OH)CO2Na; N-(2-hydroxyethyl)iminodiacetic acid (HOCH2CH2N(CH2COOH)2); L-glutamic acid (H2NCH(COOH)(CH2CH2COOH)); aspartic acid (H2NCH(COOH)(CH2COOH)); glycine (H2NCH2COOH); 1,3-diamino-2-propanolxe2x80x94N,N,Nxe2x80x2,Nxe2x80x2-tetraacetic acid (HOCH(CH2N(CH2COOH)2)2); iminodiacetic acid (HN(CH2COOH)2); mercaptosuccinic acid (HSCH(COOH)(CH2COOH)); H2N(CH2)4CH(COOH)N(CH2COOH)2; HOCH(COOH)CH(COOH)CH2COOH; (HOCH2)2CHCH2COO)xe2x88x92(NH(CH3)3)+; CH3(CH2)2CH(OH)CH(OH)(CH2)3CO2K; H2NCH2CH2OSO3Na; H2NC2H4NHC2H4SO3H; H2NC3H6NH(CH3)C3H6SO3H; (HOC2H4)2NC3H6OSO3Na; (HOCH2CH2)2NC6H4OCH2CH2OSO2OH; N-methyl-4-(2,3-dihydroxypropoxy)pyridinium chloride, ((H2N)2C6H3SO3)xe2x88x92(NH(C2H5)3)+; dihydroxybenzoic acid; 3,4-dihydroxybenzylic acid; 3-(3,5-dihydroxyphenyl)propionic acid; salts of the above amines, carboxylic acids, and sulfonic acids; and mixtures thereof.
The chemical compositions of the present invention can be made according to the following step-wise synthesis. As one skilled in the art would understand, the order of the steps is non-limiting and can be modified so as to produce a desired chemical composition. In the synthesis, the polyfunctional isocyanate compound and the polyol are dissolved together under dry conditions, preferably in a solvent, and then heating the resulting solution at approximately 40 to 80xc2x0 C., preferably approximately 60 to 70xc2x0 C., with mixing in the presence of a catalyst for one-half to two hours, preferably one hour. Depending on reaction conditions (e.g., reaction temperature and/or polyfunctional isocyanate used), a catalyst level of up to about 0.5 percent by weight of the polyfunctional isocyanate/polyol mixture may be used, but typically about 0.00005 to about 0.5 percent by weight is required, 0.02 to 0.1 percent by weight being preferred. Suitable catalysts include, but are not limited to, tertiary amine and tin compounds. Examples of useful tin compounds include tin II and tin IV salts such as stannous octoate, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin di-2-ethylhexanoate, and dibutyltinoxide. Examples of useful tertiary amine compounds include triethylamine, tributylamine, triethylenediamine, tripropylamine, bis(dimethylaminoethyl) ether, morpholine compounds such as ethyl morpholine, and 2,2xe2x80x2-dimorpholinodiethyl ether, 1,4-diazabicyclo[2.2.2]octane (DABCO, Sigma-Aldrich Chemical Co., Milwaukee, Wis.), and 1,8-diazabicyclo[5.4.0.]undec-7-ene (DBU, Sigma-Aldrich Chemical Co., Milwaukee, Wis.). Tin compounds are preferred.
A mixture of polyols can be used instead of a single polyol. For example, in a preferred embodiment a polyol mixture comprising a polyol with a water-solubilizing group and a polyol with an Rf group is used. When the polyfunctional isocyanate compound is a triisocyanate, the polyol is preferably a diol to prevent undesired gelation, which can occur when polyols having three or more hydroxyl groups are reacted with a triisocyanate.
The resulting isocyanate functional urethane oligomers and compounds are then further reacted with one or more of the monoalcohols described above. The monoalcohol(s) is (are) added to the above reaction mixture, and react(s) with a substantial portion of the remaining NCO groups. The above temperatures, dry conditions, and mixing are continued one-half to two hours, preferably one hour. Terminal fluorine-containing and/or long-chain hydrocarbon groups are thereby bonded to the isocyanate functional urethane oligomers and compounds. These oligomers and compounds are further functionalized with silane groups described above by reacting any of the remaining NCO groups in the resulting mixture with one or more of the reactive hydrogen-containing silane compounds described above. Thus, the silane compound(s) is (are) added to the reaction mixture, using the same conditions as with the previous additions. Aminosilanes are preferred, because of the rapid and complete reaction that occurs between the remaining NCO groups and the silane compound""s amino groups. Isocyanato functional silane compounds may be used and are preferred when the ratio of polyfunctional isocyanate compound to the polyol and monoalcohol is such that the resulting oligomer has a terminal hydroxyl group.
Water-solubilizing compounds can be added and reacted with NCO groups under the conditions described above in any of the steps described above. For example, as mentioned above, the water-solubilizing compound can be added as a mixture with the polyol. Alternatively, the water-solubilizing compound can be added (a) after reaction of the polyol with the polyfunctional isocyanate, (b) as a mixture with the monoalcohol(s), (c) after reaction of the polyol and monoalcohol with the polyfunctional isocyanate, (d) as a mixture with the silane, and (e) after the reaction of the polyol, monoalcohol, and silane with the polyfunctional isocyanate. When the water-solubilizing compound is a monoalcohol, it is preferably added as a mixture with the fluorine-containing monoalcohol or the long-chain hydrocarbon monoalcohol. When the water-solubilizing compound is a diol, it is preferably added as a mixture with the polyol.
When the chemical composition of the present invention contains a urethane oligomer having one or more carboxylic acid groups, solubility of the composition in water can be further increased by forming a salt of the carboxylic acid group(s). Basic salt-forming compounds, such as tertiary amines, quaternary ammonium hydroxides, and inorganic bases, including, but not limited to, those selected from the group consisting of sodium hydroxide, potassium hydroxide, cesium hydroxide, lithium hydroxide, calcium hydroxide, magnesium hydroxide, zinc hydroxide, and barium hydroxide, may be used in a sufficient amount (i.e., in an amount to maintain a pH of greater than about 6). These basic salt-forming compounds preferably can be added in the water phase, but optionally in the preparation of the urethane oligomers, to form salts with the incorporated, pendant and/or terminal carboxylic acid groups on the urethane oligomer. Examples of useful amine salt-forming compounds include, but are not limited to, those selected from the group consisting of ammonia, trimethylamine, triethylamine, tripropylamine, triisopropylamine, tributylamine, triethanolamine, diethanolamine, methyldiethanolamine, morpholine, N-methylmorpholine, dimethylethanolamine, and mixtures thereof. Preferred salt forming compounds.include those selected from the group consisting of ammonia, trimethylamine, dimethylethanolamine, methyldiethanolamine, triethylamine, tripropylamine, and triisopropylamine, since the chemical compositions prepared therefrom are not excessively hydrophilic upon coating and curing. Since certain salts formed by the reaction of salt forming compounds,- such as potassium hydroxide in combination with a carboxylic acid group, could result in undesired reaction with NCO groups, it is preferred to add the salt forming compound in a water phase after all of the diols, alcohol, and silane compounds have been reacted with the NCO groups of the polyfunctional isocyanate compound.
The molar ratios of the components of the chemical composition of the present invention are as follows:
one or more polyfunctional isocyanate compounds and one or more polyols are used in a molar ratio of from about 1:0.25 to about 1:0.45;
one or more polyfunctional isocyanate compounds and one or more monoalcohols (as discussed above) are used in a molar ratio of from about 1:0.30 to about 1:0.60;
one or more polyfunctional isocyanate compounds and one or more silanes (of formula I above) are used in a molar ratio of from about 1:0.001 to about 1:0.15; and
one or more polyfunctional isocyanate compounds and one or more water-solubilizing compounds (as discussed above) are used in a molar ratio of from about 1:0 to about 1:1.6. The preferred molar ratios are as follows:
one or more polyfunctional isocyanate compounds and one or more polyols are used in a molar ratio of from about 1:0.35 to about 1:0.42;
one or more polyfunctional isocyanate compounds and one or more monoalcohols (as discussed above) are used in a molar ratio of from about 1:0.45 to about 1:0.55;
one or more polyfunctional isocyanate compounds and one or more silanes (of formula I above) are used in a molar ratio of from about 1:0.03 to about 1:0.08; and
one or more polyfunctional isocyanate compounds and one or more water-solubilizing compounds (as discussed above) are used in a molar ratio of from about 1:0 to about 1:1.0. These molar ratios also apply to the inventive coating compositions, articles and methods.
The coating composition of the present invention comprises a solution comprising the chemical compositions of the present invention and at least one solvent. When applied as coatings, the chemical compositions of the present invention, comprising one or more urethane oligomers, impart stain-release characteristics and exhibit durability (i.e. they resist being worn-off) when exposed to wear and abrasion from use, cleaning, and the elements. In addition, the chemical compositions of the present invention are capable of improving one or more of the oil- and/or water-repellency, stain- and/or soil-repellency and soil release properties of substrates treated with the compositions.
The chemical compositions of the present invention can be dissolved in a variety of solvents to form coating compositions suitable for use in coating the chemical compositions of the present invention onto a substrate. Coating compositions preferably contain from about 0.1 to about 10 percent chemical composition, based on the weight of the coating composition. Preferably the chemical composition is used in the coating composition at about 1 to about 5 weight percent, most preferably from about 2 to about 3 weight percent. It has been found that the best stain-release properties are obtained when the coating composition is a visually clear solution. Suitable solvents include water, alcohols, esters, glycol ethers, amides, ketones, hydrocarbons, chlorohydrocarbons, chlorocarbons, and mixtures thereof. Depending upon the substrate to which the composition is being applied, water is the preferred solvent because it does not raise any environmental concerns and is accepted as safe and non-toxic.
Useful alcohol solvents include, but are not limited to, amyl alcohol, n-butanol, diisobutyl carbinol, ethanol, 2-ethylhexanol, hexylene glycol, isobutanol, isopropanol, amyl alcohol, 2-methyl butanol, n-pentanol, n-propanol, and mixtures thereof.
Useful ester solvents include, but are not limited to, amyl acetate, n-butyl acetate, t-butyl acetate, Butyl CARBITOL(trademark) Acetate (C4H9O(C2H4O)2C(O)CH3), Butyl CELLOSOLVE(trademark) Acetate (C4H9OCH2CH2OC(O)CH3), CELLOSOLVE(trademark) Acetate (C2H5OCH2CH2OC(O)CH3), methyl acetate, ethyl acetate, isopropyl acetate, isobutyl acetate, Methyl PROPASOL(trademark) Acetate (CH3OCH2CH(CH3)OC(O)CH3), n-propyl acetate, n-butyl propionate, UCAR(trademark) Ester EEP (C2H5OC2H4OC(O)CH2CH3), UCAR(trademark) Filmer IBT ((CH3)2CHCH(OH)C(CH3)2CH2OC(O)CH(CH3)2), n-pentyl propionate, and dibasic esters such as dimethyl succinate, dimethyl glutarate, dimethyl adipate, and mixtures thereof.
Useful glycol ether solvents include, but are not limited to, butoxytriglycol (C4H9O(C2H4O)3H), Butyl CARBITOL(trademark) (C4H9O(C2H4O)2H), Butyl CELLOSOLVE(trademark) (C4H9OCH2CH2OH), CARBITOL(trademark) (C2H5O(C2H4O)2H), CELLOSOLVE(trademark) (C2H5OCH2CH2OH), poly(ethylene glycol) butyl ether (ECOSOFT(trademark) Solvent PB, C4H9O(C2H4O);H), poly(ethylene glycol) ethyl ether (ECOSOFT(trademark) Solvent PE C2H5O(C2H4O)xH), poly(ethylene glycol) hexyl ether (ECOSOFT(trademark) Solvent PH C6H13O(C2H4O)2H), ethoxytriglycol (C2H5O(C2H4O)3H), Hexyl CARBITOL(trademark) (C6H13O(C2H4O)2H), Hexyl CELLOSOLVE(trademark) (C6H13OCH2CH2OH), methoxytriglycol (CH3O(C2H4O)3H), Methyl CARBITOU(trademark) (CH3O(C2H4O)2H), Methyl CELLOSOLVE(trademark) (CH3OCH2CH2OH), Propyl CELLOSOLVE(trademark) (C3H7OCH2CH2OH), and mixtures thereof.
Useful amide solvents include, but are not limited to, dimethyl acetamide, N-methylpyrrolidone, mixtures thereof, and the like. Useful ketone solvents include, but are not limited to, acetone, diacetone alcohol ((CH3)2C(OH)CH2C(O)CH3), diisobutyl ketone, isobutyl heptyl ketone (ECOSOFT(trademark) Solvent IK, (CH3)2CHCH2C(O)CH2CH(CH3)CH2CH(CH3)2), isophorone, methyl ethyl ketone, methyl n-amyl ketone, methyl isobutyl ketone, mixtures thereof, and the like.
Useful hydrocarbon solvents include, but are not limited to, toluene, xylene, mixtures thereof, and the like. Useful chlorohydrocarbon solvents include, but are not limited to, 4-chlorotrifluoromethylbenzene, 3,4-bis(dichloro)trifluoromethylbenzene, mixtures thereof, and-the like.
The preceding trademarked solvents are trademarked by Union Carbide, and are available from Union Carbide (Danbury, Conn.) or Sigma-Aldrich (Milwaukee, Wis.).
The coating compositions of the present invention can be applied as to a wide variety of substrates resulting in an article that displays durable stain-release properties. The article of the present invention comprises a substrate having one or more surfaces and on the one or more surfaces of this substrate is a cured coating derived from at least one solvent and a chemical composition of the present invention. After application and curing of the coating composition, the substrate displays durable stain-release properties.
The coating compositions of the present invention can be applied to a wide variety of substrates, including, but not limited to, hard substrates and fibrous substrates. Hard substrates include, but are not limited to, glass, ceramic, masonry, concrete, natural stone, man-made stone, metals, wood, plastics, and painted surfaces. Fibrous substrates include woven, knit, and nonwoven fabrics, textiles, carpets, leather, and paper. Substrates can have flat or curved surfaces and may be particulate and fibrous in nature, as well. Preferred substrates are capable of imbibing a liquid and are therefore porous. Such substrates are particularly subject to staining and soiling, but also benefit greatly from the chemical compositions of the present invention because the coating composition can penetrate into the porous substrate surface. Substrates comprising nucleophilic groups selected from the group consisting of xe2x80x94OH and xe2x80x94NHR, wherein R is H or lower alkyl are also preferred because they can bond to the silane groups of the chemical compositions of the present invention increasing durability. Substrates of this type include those having siliceous and metallic surfaces.
Representative examples of substrates that can be coated with the coating composition include lenses used in ophthalmic spectacles, sunglasses, optical instruments, illuminators, watch crystals, and the like; plastic window glazing; signs; decorative surfaces such as wallpaper and vinyl flooring; composite or laminated substrates such as FORMICA(trademark) brand sheeting (Formica Corp., Warren, N.J.) or laminated flooring (e.g., PERGO(trademark) brand flooring (Pergo Inc., Raleigh, N.C.)); ceramic tile and fixtures (sinks, showers, toilets); natural and man-made stones; decorative and paving stones; cement and stone sidewalks and driveways; particles that comprise grout or the finished surface of applied grout; wood furniture surface (desktops, tabletops); cabinet surfaces; wood flooring, decking, and fencing; leather; paper; fiber glass fabric and other fiber-containing fabrics; textiles; carpeting; and the like.
Since coatings prepared from the coating compositions can render metal surfaces resistant to soils, the optical properties of metal surfaces like those on decorative metal strips and mirrors can be preserved longer. The coating compositions can make wood surfaces more resistant to food and beverage stains while helping to maintain a lustrous appearance. In addition, the coating compositions can be applied as a protective coating on aircraft wings, boat hulls, fishing line, medical surfaces, and siding, and can be used in food release, mold release, adhesive release applications, and the like. Decorative stones include, for example, marble, granite, limestone, slate, and the like.
It is desirable to avoid the formation of mildew and algae on decorative stone for aesthetic and functional purposes. Application of the coating compositions of the present invention to stone eliminates the formation of mildew and algae for several months on near-horizontal surfaces.
Preferred substrates that can be coated with the coating composition of the present invention are hard, porous substrates, such as decorative and paving stones; cement and stone sidewalks and driveways; particles that comprise grout or the finished surface of applied grout, wood furniture surface (desktops, tabletops); cabinet surfaces; wood flooring, decking, and fencing; and the like.
To impart stain-release characteristics to a substrate,.having of one or more surfaces, (a) the coating composition of the present invention is applied onto one or more surfaces of the substrate and (b) the coating composition is allowed to cure (i.e. dry), preferably at ambient temperature.
Any method of application that produces a thin coating of the coating composition on the substrate surface may be used. Examples of useful application methods include, but are not limited to, spraying, padding, dipping (immersing the substrate in the coating composition), spin-coating, flow coating, and painting. When coating flat substrates of appropriate size, knife-coating or bar-coating may be used to ensure uniform coatings of the substrate.
The coating compositions can be applied to a substrate in any desired thickness. Coatings as thin as a few microns can offer excellent low surface energy, stain-resistance, and stain-release. However, thicker coatings (e.g., up to about 20 microns or more) can also be used. Thicker coatings can be obtained by applying to the substrate a single thicker layer of a coating composition that contains a relatively high concentration of the chemical composition of the present invention. Thicker coatings can also be obtained by applying successive layers to the substrate of a coating composition that contains a relatively low concentration of the chemical composition of the present invention. The latter can be done by applying a layer of the coating composition to the substrate and then drying prior to application of a successive layer. Successive layers of the coating can then be applied to dried layers. This procedure can be repeated until the desired coating thickness is achieved.
After the substrate is coated with the coating composition, the coated substrate is dried, preferably at ambient temperature or at an elevated temperature, more preferably at ambient temperature, to provide a cured coating. The coating composition is xe2x80x9ccuredxe2x80x9d when dried and the solvent is evaporated and a cured coating is provided. This cure preferably takes place at approximately 15 to 35xc2x0 C. (i.e. ambient temperature) until dryness is achieved, up to approximately 24 hours. During this time and over a subsequent period of time, the chemical composition can also form chemical bonds with the substrate and between molecules of the chemical composition.
The resulting coated substrates coated with a cured coating, derived from at least one solvent and a chemical composition of the present invention, have been found to be non-staining and/or to release stains with simple washing methods. The cured coating of the chemical compositions of the present invention have also been found to be durable and hence to resist being worn-off due to wear and abrasion from use, cleaning, and the elements.